The present invention relates to an apparatus for automatically changing bobbin cases in quilting machines.
It is known that in quilting machines, quilting operations are performed by one or more sewing machines which are installed on a frame which moves with respect to the cloth to be quilted. The sewing machines have a conventional structure, with a head which lies above the cloth and is designed to move the needle that feeds the upper thread and a hook assembly which moves below the cloth synchronously with the needle and around a supporting case which rotatably accommodates a bobbin on which the lower thread is wound; said lower thread, together with the upper one fed by the needle, forms the stitch.
Owing to the high productivity of current quilting machines, the bobbins of the lower thread empty rather quickly and must be replaced frequently with full bobbins. The bobbins are currently usually replaced manually, with prolonged interruptions of the production cycle and considerable reductions in performance.